ARC: Add PCI support

Add PCI support to ARC and update drivers/pci Makefile enabling the ARC
arch to use the generic PCI setup functions.

[bhelgaas: fold in Joao's pci-dma-compat.h & pci-bridge.h build fix (I
should have caught this myself, sorry]
Signed-off-by: Joao Pinto <jpinto@synopsys.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>

arch/arc/kernel/pcibios.c

@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2014-2015 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/pci.h>
+
+/*
+ * We don't have to worry about legacy ISA devices, so nothing to do here
+ */
+resource_size_t pcibios_align_resource(void *data, const struct resource *res,
+				resource_size_t size, resource_size_t align)
+{
+	return res->start;
+}
+
+void pcibios_fixup_bus(struct pci_bus *bus)
+{
+}